Given an input string, reverse the string word by word.
For example,
Given s = "the sky is blue",
return "blue is sky the".
思路
用stack 或者 遍历时从后往前遍历
注意
给定的string可能是由多个空格隔开的,直接用slipt(" ")会得到[, , , a, , , b]
,不是我们想要的。
必须用s.split("\\s+")
这样split多个空格
public class Solution {
public String reverseWords(String s) {
if (s == null || s.length() == 0) {
return s;
}
//split by multiple space
String[] temp = s.split("\\s+");
System.out.print(Arrays.toString(temp));
StringBuilder result = new StringBuilder();
for (int i = temp.length - 1; i >= 0; i--) {
result.append(temp[i]).append(" ");
}
String res = result.toString();
return res.trim();
}
}